Electric or mechanical water pump?

[Randy Folsom]

View attachment 140790

Paul,

Thx for the guidance. I don’t quite understand the connection between the overflow tank and the suction side of the pump. I am guessing there needs to be a way to ensure that it doesn’t cause too much coolant to bypass the radiator loop.

Cheers, Randy

 

[Paul Hendrickx]

Wow Paul,
Thanks for the great explanation!
I always like to keep things as simple as possible. Of course, the combination of swirlpot and expansion tank from Concept Racing would be ideal.
In my car, it's all about engine cooling, I don't have heating or air conditioning.
If I understand everything correctly, such a combination swirlpot would be sufficient, e.g. on the firewall, without any further opening in the cooling circuit. Possibly another bleeder screw at the front of the radiator for filling.

The system could look like this:
Engine water outlet -> electric water pump -> up to the swirlpot -> down to the radiator -> back to the engine.

that sounds almost too simple now...

 

[Paul Hendrickx]

engine coolant out----swirltank----radiatior in---- radiator out---- water pump as low and close-by the engine...
bleedline from radiator to (with restrictorof 3mm) expansion tank

 

[Paul Hendrickx]

Paul,

Thx for the guidance. I don’t quite understand the connection between the overflow tank and the suction side of the pump. I am guessing there needs to be a way to ensure that it doesn’t cause too much coolant to bypass the radiator loop.

Cheers, Randy

if you connect te expansion tank is to the pressure side you will presurerise the tank.

 

[Randy Folsom]

Paul,

I got the 400 because it has double the capacity of the 200 which it replaced and the mounting bosses are better situated.

I just learned that if you get a 400 it will need to be an older model (eBay or a junk yard). According to Tecomotive, the newer models are not compatible with PWA controllers.

Tecomotive - Pierburg CWA400 LIN

Tecomotive develops and sells unique electronic devices for use in vehicles of all kinds.

www.tecomotive.com

Cheers, Randy

 

[H.J.Bayer]

engine coolant out----swirltank----radiatior in---- radiator out---- water pump as low and close-by the engine...
bleedline from radiator to (with restrictorof 3mm) expansion tank

Thank you Paul.
This arrangement makes more sense, you're right.
If you use a combined swirlpot/expansion tank, it has to sit high in the engine compartment.
But then it will be difficult with a bleeding line from the radiator at the front to the rear

 

[Paul Proefrock]

OK, I'm sold on the CWA400 pump but as I research purchasing, I am seeing a lot of knock-offs. Amazon has them from $89 to $548. Few if any are identified as Pierburg pumps. Most all are foreign-made units, which I am very skeptical.

Has anyone had any experience with any of the clones? Is there one that is preferred? Randy mentioned he purchased a reconditioned one but I don't see any reconditioned units.

The video he provided the link for comments about the $100 water pump. But when you follow the link to Amazon, it turns into a $389 pump.

Any recommendations?

 

[Brian Kissel]

I bought right direct from Germany. Amazon kept coming up with strange things so bought direct. And they don’t rip you off on shipping. If I remember correctly, I had it in about a week. I haven’t used the first one yet, but I’m thinking about a spare.

Regards Brian

 

[Randy Folsom]

OK, I'm sold on the CWA400 pump but as I research purchasing, I am seeing a lot of knock-offs. Amazon has them from $89 to $548. Few if any are identified as Pierburg pumps. Most all are foreign-made units, which I am very skeptical.

Has anyone had any experience with any of the clones? Is there one that is preferred? Randy mentioned he purchased a reconditioned one but I don't see any reconditioned units.

The video he provided the link for comments about the $100 water pump. But when you follow the link to Amazon, it turns into a $389 pump.

Any recommendations?

I think I just got lucky with the price because the packaging was damaged. I would not take a chance on non-OEM.

 

[Pat]

I just bought it direct from their site in Germany and got it yesterday because like others said too many knock offs out there.

 

[Pat]

Okay so I have the CWA400 pump and I put a plate adapter on the engine where the water pump would normally mount and it has 12AN female ports for coolant. I’m wondering what fittings people are using for these coolant lines? 12AN on the block to what size for the hose? Seems like even using larger coolant lines that this reduction to 12AN would cause backup? Obviously 12AN would be too small to run through out and I’m assuming if I need to mount the remote pump low and near the engine I would need 90s coming off the block pointing down? Thanks again for the help. I’m trying to do this with the engine on the floor so the routing is all in my head. With the mounts built for alt and AC I’m quickly running out of room around the coolant holes.

 

[JP Verweij]

Why would you put the pump near the engine?
Usually, electric pumps go after the rads exit so thats up front in a GT40.

 

[Joel Heinke]

See this thread: https://www.gt40s.com/threads/electric-water-pump-how-to.57366/
as it likely answers your questions. My Miura has 1 1/2" aluminum tube to carry coolant to/from the engine to the radiator.

 

[Randy Folsom]

Mounting a CWA pump up front is just about impossible because of the orientation of inlet, outlet and electrical connection. I designed this mount to place it on the tub wall as low as possible.

I just received the parts from Send-Cut-Send. I hope to have it assembled this week.

I am also using a water pump from a Ford Explorer. It’s lower profile than the typical shorty. The impeller and shaft mount are replaced with a welded on plate. The inlet fits nicely below the alternator and above the harmonic balancer.

I’ll post updates after it’s installed.

 

[Randy Folsom]

It turns out that the Explorer also uses a unique timing chain cover so unfortunately, the Explorer water pump doesn’t work on typical SBF timing covers.

I am now working out how to make the Davis Craig manifold work with the Pierburg pump.

A complicating issue is that the DS manifold has to have the inlet clocked down towards the driver side and the non-clockable Pierburg pump has to be mounted on the passenger side.

My plan is to mount the pump on the passenger side of a cross brace that runs from one side of the tub to the other. Then run a hose in a gentle sweep under the harmonic balancer and up to the manifold’s inlet.

 

[Pat]

Mounting a CWA pump up front is just about impossible because of the orientation of inlet, outlet and electrical connection. I designed this mount to place it on the tub wall as low as possible.
View attachment 142160
I just received the parts from Send-Cut-Send. I hope to have it assembled this week.

I am also using a water pump from a Ford Explorer. It’s lower profile than the typical shorty. The impeller and shaft mount are replaced with a welded on plate. The inlet fits nicely below the alternator and above the harmonic balancer.
View attachment 142162

I’ll post updates after it’s installed.

Would love to get a copy of the file for the mount you made for the pump. Looks like we’re going the same direction with pump and water pump plate.

Pat

 

[Randy Folsom]

Would love to get a copy of the file for the mount you made for the pump. Looks like we’re going the same direction with pump and water pump plate.

Pat

Pat, I will post the files here after I prove to myself it works. That will be in about a month as I have trips to Japan and Las Vegas coming up.

I am also looking into installing a cross brace that runs from side to side in front of the engine. The idea is to position the pump slightly to the right of the center line right in front of the oil pan such that pump inlet is closely aligned with the coolant tube in the spine. Still not a lot of options with regards to the rotation because of the connector and outlet orientation.
Cheers, Randy

 

[Pat]

Thanks, Randy. I still haven’t dropped my engine in yet and was hoping the Pier rug would be able to mount on the DS low somewhere but I guess from your post there is no room.

 

[Randy Folsom]

Thanks, Randy. I still haven’t dropped my engine in yet and was hoping the Pier rug would be able to mount on the DS low somewhere but I guess from your post there is no room.

There’s some room on the DS below and in front of the AC compressor, but it is tight and the pump’s orientation is more awkward. I plan to use the DS for my remote oil filter mount. Even if the oil filter is mounted in the back, it’s easier if the lines go forward first to avoid the engine mount.